Wireless communication systems have been deployed in virtually all metropolitan areas of the world. Likewise, access to the Internet has also increased in popularity. Each of these systems facilitate communication between users of the same systems, but there has been somewhat of a barrier in voice communication between users of one system with users of the other system. Voice communication over the public Internet between computer users is presently available and somewhat widely practiced.
A primary concern for connecting the two systems to facilitate voice communication between users of one system with users of another system is the difference in the way voice data is transmitted. In standard telephone communication voice signals are band limited to about 4 Khz and then digitized and encoded using pulse code modulation (PCM). This produces a stream of data that can be transmitted from one point to another point over a public switched telephone network, for example. In digital wireless systems more aggressive compression encoding schemes are used such as, for example, vector sum excited linear predictive coding (VSELP).
Mobile wireless systems already interface with public switched telephone networks, so a conversion from the compression used to carry the wireless signal to PCM, and vice-versa, is already in use. Making local calls with wireless phones usually only incurs an air time charge, and most long distance calls still incur a long distance charge. The use of so called voice over IP telephone software used to connect two internet users for voice communication circumvents such long distance charges, but wireless phone users have no such option. Therefore there is a need for which users of wireless and mobile communication devices can connect with other remote users over the Internet.